1. Field of the Invention
The present invention relates generally to nuclear reactors, and more particularly to a self-supporting pipe rupture and whip restraint system employed in conjunction with, for example, the high-pressure main steam line or process pipe of a nuclear reactor steam generator pressure vessel in order to contain the highpressure, high-temperature process steam, as well as to prevent whipping of the process pipe, under process pipe rupture conditions.
2. Description of the Prior Art
Recent requirements and regulations, issued by the Nuclear Regulatory Commission (NRC) with respect to the design or structural arrangement of nuclear reactor power plant safety grade structures, components, and systems, have decreed that rupture conditions must be postulated in connection with any one of the safety grade piping components, and that in light of such postulated rupture conditions, structural means must be incorporated into the piping systems which will render the same capable of sufficiently accommodating and adequately protecting the safety grade structures, components, and systems from the dynamic load effects, process fluid effluent, and pipe whipping attendant an exemplary or typical postulated pipe rupture. In particular, for example, the nuclear reactor primary coolant loop component, the emergency coolant systems, and the various reactor control systems must be preserved intact such that substantially normal, continued operation of the reactor facility, without any critical malfunctions, shutdowns, service interruptions, activations of the facility's elaborate back-up, redundant, or secondary safety systems, or the like, can be achieved despite the aforenoted postulated or anticipated occurrence of a piping component rupture.
The aforenoted requirements and regulations issued by the NRC were effectuated upon a retroactive basis applicable to all nuclear reactor facilities already in existence at the time that the requirements and regulations were promulgated. In addition, of course, all nuclear reactor facilities which were currently under construction at the time the requirements and regulations were issued, as well as all facilities which would be erected in the future, were subject to, and would therefore have to comply with, the criteria set forth in such requirements and regulations.
In compliance with the aforenoted requirements and regulations, massive whip restraint structures were erected within existing conventional nuclear reactor facilities. The structures comprised, for example, vertically extending truss type frameworks or towers disposed parallel to and adjacent the piping components. The structures extended, in some instances, approximately one hundred (100) feet above the facility floor or foundation, and were fabricated from large structural I-beam members, channel irons, angle irons, and the like. The structural members or components were secured about the piping components in their restraining modes by means of large clamping fasteners, or alternatively, conventional clamshell structures were employed. As may be appreciated, these massive whip restaint structures were structurally complex and extremely expensive to erect. In addition, due to the requisite size and vertical extent of these restraint structures, structural analysis of such structures dictated that the bases or foundations of the structures be substantially more massive and larger than the upper portions of the structures. This increased size within the vicinity of the tower or framework bases drastically limits or reduces the space available for other system components of the facility, in addition to hindering the ingress and egress of maintenance personnel. Still yet further, and probably most importantly, while the aforenoted tower or truss-type framework restraint structures served to restrain the piping components in whip-restraint modes, they nevertheless could not prevent the pressurized discharge of the process fluid effluent from the piping component should the same in fact experience a rupture condition. This uncontained, unconfined discharge of the process fluid would of course result in dire consequences with respect to the continued operation of the nuclear reactor facility.
Accordingly, it is an object of the present invention to provide a new and improved pipe rupture and whip restraint system.
Another object of the present invention is to provide a new and improved pipe rupture and whip restraint system which is particularly adaptable for use within a nuclear energy reactor facility.
Still another object of the present invention is to provide a new and improved pipe rupture and whip restraint system which is particularly adaptable for use in conjunction with a high-pressure, high-temperature process fluid line of a nuclear energy reactor facility.
Yet still another object of the present invention is to provide a new and improved pipe rupture and whip restraint system which overcomes the various disadvantages of the conventional pipe whip restraint systems.
Still yet another object of the present invention is to provide a new and improved pipe rupture and whip restraint system which is self-supporting, thereby eliminating the requirement for specially designed and erected auxiliary supports or restraints.
A further object of the present invention is to provide a new and improved pipe rupture and whip restraint system which is integrally fixed to, and fabricated with, the high-pressure, high-temperature process fluid pipe in conjunction with which the pipe rupture and whip restraint system of the present invention is being employed.
A yet further object of the present invention is to provide a new and improved pipe rupture and whip restraint system which can adequately sustain the dynamic forces of the process fluid and the whipping of the process fluid pipe under pipe rupture conditions.
A still further object of the present invention is to provide a new and improved pipe rupture and whip restraint system which can in fact contain the process fluid internally within the piping component system even in view of a rupture condition manifesting itself within the process fluid pipe per se.
A yet still further object of the present invention is to provide a new and improved pipe rupture and whip restraint system which is relatively simple in its structural constitution, relatively inexpensive to fabricate.
A still yet further object of the present invention is to provide a new and improved pipe rupture and whip restraint system which is easily capable of being spatially accommodated within the reactor facility so as not to hinder the spatial accommodation of other structural components within the facility, and which does not similarly hinder the ingress or egress of the various nuclear energy reactor facility maintenance personnel.